1. Field of the Invention
The present invention forms part of the general framework of the combining of radioelectric functions in aircraft.
It can be applied especially to the making of an aircraft antenna according to the known technology of multilayer printed circuits combining, on the one hand, the functions of satellite localization of systems working in the L band of the radioelectric frequencies, known as the Global Positioning System or GPS L1 and the Global Navigation Satellite System or GLONASS and, on the other hand, the landing assistance function in the C band of radioelectric frequencies working in the Omni MLS or Microwave Landing System.
2. Description of the Prior Art
At present, the antennas related to these functions are distinct and have different technologies. If we consult the catalogs of the aeronautical antennas by RAYAN and M/A-Com, it can be seen that antennas designed for the MLS Omni system are "quarter-wave whip" type antennas while the radiating elements of the GPS L1 or GLONASS system are formed chiefly by monolayer microstrip structures of the printed-circuit patch type on substrates with high dielectric permittivity. Furthermore, when it is proposed to obtain the GLONASS function through the GPS antenna, its performance characteristics are not certified.
The aim of the invention is to overcome the above-mentioned drawbacks by proposing a single multilayer antenna structure that is very compact, adapted to aeronautical constraints and complies with the specifications of the GPS L1, GLONASS and Omni MLS functions when they are taken separately.